First, prepare the marinade by combining soy sauce, honey, brown sugar, apple cider vinegar, minced garlic, grated ginger, sesame oil, and black pepper in a large mixing bowl. Whisk until everything is well blended.
Place the chicken thighs in a resealable plastic bag or a shallow dish, and pour the marinade over them. Make sure each thigh is fully coated. Seal the bag or cover the dish, and refrigerate it for at least 4 hours. If you can, leave it overnight to truly soak in the flavors.
Before grilling, preheat your grill to medium-high heat, aiming for about 375–400°F. If you’re using a charcoal grill, wait until the coals are evenly lit with a layer of white ash. Clean the grates thoroughly using a grill brush to ensure your chicken doesn’t stick.
Remove the marinated chicken thighs from the bag and shake off any excess liquid. Place the thighs skin-side down on the grill over direct heat. Allow them to sear for 3–4 minutes until you see beautiful grill marks. Move the chicken to indirect heat and close the lid. Cook for another 25–30 minutes, turning occasionally and basting with the leftover marinade. Use a meat thermometer to check that the internal temperature hits 165°F.
Once the thighs are cooked, remove them from the grill and allow them to rest for 5 minutes. This keeps the juices locked in, delivering maximum flavor.